Wheel-spoke die and method of its use



2 Sheets-Sheet 1 Filed July 16-, 1921 H. P. ARNT ET AL WHEEL SPOKE DIEAND METHOD OF ITS USE m 2 t w are .m h a Q i .w m gm 2 a v V. Ww m 9 Q lI :EH. 5 4 7 fl Patented Dec. 2, 1924.

UNITED STATES PATENT OFFICE.

HERALD P. ARNT AND THOMAS N. AIKENS, 01' LAKEWOOD, OHIO.

WHEEL-SPOKE DIE AND METHOD OF ITS USE.

Application filed July 16, 1921.

To all whom it ma concern:

Be it known t at we, HERALD P. ARNT and THOMAS N. AIKENs, citizen of theUnited States of America, and subject of the King of Great Britain,respectively, residing at 1552 Robinwood Avenue and 1564 Wagar Avenue,respectively, city of Lakewood, in the county of Cuyahoga and State ofOhio, have invented a new and useful Improvement in Wheel-S oke Dies andMethods of Their Use, of w ich the following is a specification, theprinciple of the invention being herein explained and the best mode inwhich we have contemplated applying that principle, so as to distinguishit from other inventions.

Our invention relates to a combined blanking and forming die adaptedpartially to produce a one-piece tubular wheel spoke, as well as to themethod of its operation.

We are wellaware, that owing to the growing scarcity and therefore risincost of Wood having the properties whic are adapted to withstand thesevere stresses to which wheel spokes are subjected, hollow metal spokeshave already come into vogue; indeed, we have ourselves been for sometime engaged in the manufacture of tubular wheel spokes. We have learnedfrom experience that the trade is strongly inclined to favor andaccordingly it is the object of our present invention to manufacture anintegral tubular wheel spoke resembling in shape the well knownconventional design of wooden spoke.

Adverting to the drawings:

Figure I is a vertical longitudinal section through the middle of ourimproved die, feasibly mounted on a press, certain parts being shown inelevation.

Fig. II is a plan section taken on line II-II of Fig. I, one half of thedie being shown as a plan view, punch not shown.

Fig. III is a section on line III-III of Fi II.

ig. IV is a section on line IVIV of Fig. II.

Fig. V is a section on line VV of Fig. II.

Fig. VI is a view similar to Fig. V with the die shown 0 en.

Inasmuch as t e necessary parts, by means of which our die is suitablymounted and caused to be operated, are with the possible exception ofminor details, old and well known to the art, a very cursory descriptionSerial No. 485,354.

of the parts of the press will be deemed sufficient.

A bolster plate 1 has over it a bottoni shoe 2 and in spaced relation tothe latter a top shoe 3, their relative position being determined andcontrolled by means of guide pins 4 mounted in appropriate bushings 5.The usual stripper plate'6 is positioned just above the space to be occuied by sheet metal and above the blanking die 7 with its shearing edge8.

It will be apparent from the drawings that the blanking die is duplexsided and inasmuch as its opposed conformation walls are symmetricalonly one-half of the blanking die need be described and therefore thesingular" number will be hereinafter employed. A draw punch orstationary forming die 9 is located within the blanking die 7 and has anupper contour clearly to be seen in Figure I. It is of elongated formand its upper surface includes at one end a flat section 10 slopingupwardly in a direction away from the near end, which surface 10terminates at a peak 11 which may be considered as a straight crosswiseextending line. Thereafter, the top surface of the forming die 9,continuing in a direction toward its opposite end slopes rather abruptlydownward toward such other end at 12. In consequence, the peak line 11makes what may be considered as an upwardly projecting shoulder. Thesurface 12 is curved and merges with a conical surface 13 ofconsiderable longitudinal extent to constitute the main or mlddleportion of the spoke. It is to be understood that the employment of aconical surfaced forming die over the extent shown is a mere arbitrarypreference as against having this middle portion of it semi-cylindrical.A comparatively short distance from the o posite end of the forming di.it is presse along a curved surface 14 to form an arcuate orsemi-circular shoulder 15. The correspondin end of the forming die is ofsemi-cylindrical form at 16 and with that surface the curved surface 14merges.

As an aid in distinguishing we have desi ated as B the sheet steel fromwhich 1: 1e blanks are to be out. The operations of the dies shown inthis application will leave the blank about half formed. Subsequentoperations for finishing the spoke form will be performed by a trimmingdie and a final forming die to constitute the subject matter of ourseparate applications bearing Serial Numbers 485,352 and $85,353 andfiled of even date herewith.

A blanking punch 17 having the lateral contour 17 shown in Fig. II firstacts to shear the blank along a line corresponding to the edge 17 at theshearing edge 8. Continuing downwardly each of the sections of theblanking punch 17 draws the spoke blank down on opposite sides of theforming die as disclosed in Fig. V. In so doing the inner or nave end ofthe spoke blank I) is bent downwardly away from a line b which isdirectly over the peak 11, to be flattened by an inclined punch wall 18against the surface 10 of the forming die. Simultaneously, a portion 6is pressed downwardly along a curved line correspond ing to the surface12 of the forming die.

During the latter stage of the pressing movement a major middle sectionb of the blank is curved about the conical surface 13 and is set bymeans of a forming punch 19 interposed between the sections of the blanking punch 17 as appears in Fig. III. The outer or felloeend of the spokeblank commencing at If ever the shoulder 15 is pressed along a curve 6against the surface 14 to terminate as a semi-cylindrical surface 6 bypressing around the surface 16; the surface 2-0 of forming punch shownin Fig. IV serving to accomplish this purpose.

The bottoms of the blanking punch 17 engage in the usual way pressurepads 21 which actuate pressure pins 22 which in turn depress a plate 23against the action of springs 24:, these pressure pads serving to ironout the spoke as it is being formed. Operated downwardly through the topshoe 3 by engagement with a suitable stop (not shown) is the ordinaryknock-out pin 25 to actuate the forming punch 19 which serves as aknock-out pad, as will be readily understood to release the formedblank.

We claim 1. The procedure in the method. of male ing a hollow wheelspoke from sheet metal which consists in first bending opposite ends ofa blank downwardy about a line and then forming it to concaro-convexshape in both directions from the plane in which said line lies and sothat one end is of pro gressii 'ely reduced dimensions.

2. The procedure in the method of malt-- ing a hollow wheel spoke fromsheet metal which consists in first bending opposite ends of a blankabout a straight line extending crosswise of the longitudinal dimensionof the blank and then forming it to arcuate form on one side of saidline and. to angular form on the other side of said line.

3. The procedure in the method of making a hollow wheel spoke from sheetmetal which consists in first bending opposite ends of a blank about astraight line extending crosswise of the longitudinal dimension of theblank nearer one of its ends and then forming it to angular form in adirection toward the end nearest said line and to arcuate form on theopposite side of said line.

4. A forming die having a surface at one end flat and having nearer itsother end a straight raised line extending across from one side to theother, the other end of said die being of concave form, opposite ends ofsaid die sloping downwardly in directions away from said raised line.

Signed by us, this 5th day of July, 192i.

HERALD P. ARNT. THOMAS N. AIKENS.

